diff --git a/steps/DP3.PreflaggerStepGenerator.cwl b/steps/DP3.PreflaggerStepGenerator.cwl
index 7b29b255eb61e6d2d4e982b255f4adc0d2cb514a..03f6c11d6f16db4d72a38666e4a294a2f568fb28 100755
--- a/steps/DP3.PreflaggerStepGenerator.cwl
+++ b/steps/DP3.PreflaggerStepGenerator.cwl
@@ -21,8 +21,7 @@ inputs:
       .flagstat. The basename of the table is the MS name (without extension)
       followed by the stepname and extension.
   - id: count.path
-    default: ''
-    type: string
+    type: string?
     doc: >-
       The directory where to create the flag percentages table. If empty, the
       path of the input MS is used.